Extrusion can be cold or hot, depending on the alloy and the method used. This article focuses on the direct hot extrusion and describes a typical sequence of operations for the direct extrusion of a solid section. It discusses the key variables of extrusion process, including extrusion speed and extrusion exit temperature. The article reviews the classification of extrusion presses: direct, direct for seamless hollow, and indirect. The functions of the press dies and tooling are presented in a table. The article discusses the extrusion of soft and medium-grade alloys, hard alloys, and aluminum-matrix composites. It reviews common aluminum extrusion defects, including surface defects, blisters, and internal cracking. The article concludes with a discussion on the drawing of solid section and aluminum tube.
This article discusses two basic forms of extrusion: cold and hot. It provides information on three types of extrusion processes, namely, direct extrusion, reverse extrusion, and hydrostatic extrusion. The article also discusses the mechanics, analysis, tooling and die design of extrusion as well as thermodynamics. The finite-element method suitable for simulation of metal forming processes is explained. The article examines the extrusion defects that are divided into three different categories including surface, subsurface, and internal type. It includes information on friction and lubrication modeling of extrusion processes. The article also discusses the fundamentals of extrusion technology of titanium alloys and aluminum. It concludes with information on two forms of wear in extrusion, namely, adhesive and abrasive wear.